Who was Leonhard Euler and what did he discover?

Leonhard Euler was an 18th-century Swiss polymath widely regarded as one of the most prolific mathematicians and scientists in history. Active in Saint Petersburg and Berlin, he founded the studies of graph theory and topology, introduced core mathematical notations like f(x) and i, and contributed extensively to physics, astronomy, and engineering. His massive output of 866 publications is currently being collected in the Opera Omnia.

What we know

• Leonhard Euler was a Swiss polymath who worked as a mathematician, physicist, astronomer, logician, geographer, music theorist, and engineer. [1, 2]
• He founded graph theory and topology, partly through his solution to the Seven Bridges of Königsberg problem. [2]
• Euler introduced standard modern mathematical notations including f(x), i for the imaginary unit, pi for the circle ratio, and Sigma for summations. [2]
• His complete scientific production is collected in the multi-volume Opera Omnia, managed by the Euler Committee. [2, 4]

Where to go next

• a case in pointWhat was the Seven Bridges of Königsberg?
• how we knowHow is the Opera Omnia published?
• whoWho was Johann Albrecht Euler?
• the bigger pictureWhat did Swiss mathematicians achieve in the 18th century?
• what followedHow did Euler impact modern physics and fluid dynamics?
• an unexpected connectionHow is Leonhard Euler connected to a Nobel Prize-winning biochemist?Hans von Euler-Chelpin, who won the 1929 Nobel Prize in Chemistry for investigating sugar fermentation, was distantly related to Leonhard Euler.

Sources

• [1]Leonhard Euler (Wikidata Q7604) · CC0 1.0
• [2]Leonhard Euler · CC BY-SA 4.0
• [3]Johann Euler · CC BY-SA 4.0
• [4]Euler Committee of the Swiss Academy of Sciences · CC BY-SA 4.0
• [5]Hans von Euler-Chelpin · CC BY-SA 4.0